665545545566 has 32 divisors (see below), whose sum is σ = 1093340959200. Its totient is φ = 301336358400.

The previous prime is 665545545551. The next prime is 665545545583.

It is a happy number.

665545545566 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 665545545499 and 665545545508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18757010 + ... + 18792458.

It is an arithmetic number, because the mean of its divisors is an integer number (34166904975).

Almost surely, 2^665545545566 is an apocalyptic number.

665545545566 is a deficient number, since it is larger than the sum of its proper divisors (427795413634).

665545545566 is a wasteful number, since it uses less digits than its factorization.

665545545566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38780.

The product of its digits is 324000000, while the sum is 62.

The spelling of 665545545566 in words is "six hundred sixty-five billion, five hundred forty-five million, five hundred forty-five thousand, five hundred sixty-six".